Automatic counter reverse



Jan. 15, 1946.

R. a BIOYDVEN 2,393,018

AUTOIATIC I COUNTER REYERSE MECHANISM Filed July 29, 1942 7 Sheets-Sheet1 FIE J OOOOOQOOOOOOOOOOO INVENTQR PM" 50mm ATTORNEYS Jan. 15, 1946. EBY5 N 2,393,018

AUTOIA'I'IC COUNTER REVERSE MECHANISM Filed July 29, 1942 Y 7Sheets-Sheet 2 TIE EA- INVENTOR ATTOkNEYS Jan. 15, 1946. j R. a BOYDEN2,393,018

' AUTOMATIC QOUNTER REVERSE MECHANISM Filed July 29, 1942 7 Sheets-Sheet3 Fig.4.;

IN VE NTOR Fewer f. fiovmv ATTORN EYS Jan. 15, 1946. R. E. BOYDE N;

AUTOMATIC COUNTER REVERSE MECHANISI Filgd J uly 29, 1942 7 Sheets-Sheet4 INVENTOR PM [T fiovmy ATTORN EYJ Jan. 15, 1946. R. E. BOYDEN 2,393,018

AUTOMATIC COUNTER REVERSE MECHANISM Filed July 29, 1942 '7 Sheets-Sheet5 INVENTOR Foal-WE. 50mm ATTORN EYJ Jan. 15, 1946. RQ E BOYDEN 2,393,018

AUTOMATIC COUNTER REVERSE MECHANISM Filed July 29, 1942 7 Sheets-Sheet 6INVENTOR Paar [T 50mm BY WMM ATTORNEYS Jan. 15, 1946. R. E. BOYDENAUTOMATIC COUNTER REVERSE MECHANISM Filed July 29, 1942 7 Sheets-Sheet 7ATTORNEYS Patented Jan. 15, 1946 AUTOMATIC COUNTER REVERSE IMECHANISMRobert E. Boyden, Los Angeles, Calif., assignor to Marchant CalculatingMachine Company, a corporation of California Application July 29, 1942,Serial No. 452,679

7 8 Claims. (Cl. 235-79) The present invention relates tocalculatingmachines and the like having registering-means to displayfactors and results of calculations, and has particular reference to amachine of this class capable of performing the four cardinalcalculations, and wherein the registering means may be caused to displaythe result of a calculation, either as a true figure or as a complementof that figure.

\ It is well known that in order to obtain a true The manner in whichthe foregoing together with additional objects and advantages of theinvention are accomplished willbe best understood from the followingdescription of a preferred embodiment thereof when read in conj unctionwith the accompanying drawings, in which:

figure registration of the multiplier in a multipiie cation operation itis necessary that the dials of the quotient and multiplier'register.commonly called the counter dials, be driven in the same direction asthe accumulator dials are driven, while toobtain a true figureregistration of a quotient in a division operation it is necessarythat'the counter'dials be driven in the opposite direction to that inwhich the accumulator dials are driven. 0n the other handin order-toobtain a complementary registration of a multi-' plier in'multiplication operation. the counter dials must be driven in adirection opposite to that in which the accumulator dials are driven,

Automatic control devices for insuring that the counter dials will bedriven in the proper direction with respect to the accumulatordials inany selected class of calculation have previously been provided. Ingeneral, such devices are eifective to set the counter reversingmechanism as an incident to the initiation of each calculation and torestore it to its initial setting at the conclusion of each calculation.This requires that such devices include both a counter reverse settingmeans and a counter reverse restoring means, rendering them complex inconstruction and also resulting in many useless operations of thesetting means, the restoring means, and the counter reversing means, byreason of the 'fact that restoring and setting occur unneoessarilyFigure 1 is a plan view of the calculating machine embodying the presentinvention;

Figure 2 is a side view illustrating the setting clutch and controlstherefor;

- Figure 2A is a detail side view of the device operable during certainphases of division operations for causing engagement of the settingclutch;

Figure 3 is a side view of the main clutch and I controls therefor:

Figure 4 is a side view or the restore clutch and controls therefor; v

Figure 5 is'a side ;view of the motor circuit control associated withthe main clutch and the setting clutch;

Figures 6 and? are side views illustrating the mechanism for dipping andlatching the accumulator register with its driving gears meshing withthe actuator gears: a

Figure 7A is a detail side view of part of the division key returningmechanism;

Figure 8 is a side view illustrating part of the division controlmechanism, particularly that utilized in connection with control of thecarriage shifting means;

Figure 9 is a side view illustrating the control of the division controlmember by the division initiating key, the relationship between thedivision control member and the restore clutch mechanism, and the meanscontrolled by the accumulator register for tripping the main clutch doglatch;

Figure 10 is a side view illustrating part of the stop key mechanism;

Figure 1-1 is a side view illustrating part of the stop key mechanismand the division control mechanism;

Figure 12 is a side view illustrating the counter, the actuatortherefor, and the control means for the counter actuator-constructed inaccordance with the present invention? Figure 13 is a detail side viewsimilar to Figure 12 illustrating certain of the elements in an titerindetail in the Avery Patent 2,216,659, to which reference may be made fora full-disclosure of the machine as a whole. only a brief description ofthe I operation of the same will be included herein; it being noted thatparts shown but not described herein may be found described in saidpatent, with identical reference numerals applied thereto.

The machine is of the proportional gear, selective speed, type whereinthere is provided a series of gear combinations (not shown) of differentgear ratios in each order. The usual banks of keys I00 (Figure 1) areprovided, one for each order, to control the connection of one of thegear combinations, depending on the value of a key depressed, to acyclically operable actuator including a main clutch 420 (Figure 3) andthereby transmit rotation to a series of ordinally p0- sitioned drivegears l89 (Figure 6). During actuation, intermeshing gears 2H and 213supported on pivot rods 212 and'2l0, respectively, carried by thecarriage 250 and aligned with the various ordinal'gears I89, areentrained with these gears to transmit rotation to accumulator dials 219forming an accumulator register 3I0 (see Figure 1). As disclosed in theabove mentioned Avery Patent 2,216,659, tens carry mechanism (not shown)of the duplexing type is provided to effect tens transfer.

The ratios of the various above mentioned gear combinations are suchthat for each cycle of operation of the actuator, the dials 219 willeach be driven at a rate of speed proportionate to the value of thedepressed key I00 in line therewith, plus an added increment ofone-tenth of the amount of rotation of the next lower order dial. Thus,during each cycle of operation of the main clutch 420 an amountcorresponding to the amount set up inthe keyboard will be entered intothe accumulator register if! and, through mechanism to be disclosedhereinafter, the number of cycles of operation of the main clutch ineach carriage position will be entered into appropriate dials I 815(Figure 12) of a counter register I800 (see Figure 1) so that duringdivision the counter register I800 serves to register the quotient of aproblem, while during multiplication the register. I800 registers themultiplier and during addition this register registers the number ofadditions performed.

Setting clutch control Engagement of the main clutch is effected by asetting clutch 430 (Figure 2) keyed on a settingfects certainpreliminary operations incident to the commencement of a calculationunder power of the machine motor besides causing' engagement of the mainclutch to effect actuation.

The setting clutch is normally held disengaged by a clutch dog 394(Figure 2) which is keyed on a rockable shaft 5M and is urged clockwiseby a spring 522 tensioned between the machine frame and the dog so as tourge its rightmost end, as viewed in Figure 2, into its illustratedposition wherelnitseatsinmeofapairof diametrically opposed notchesformed in the clutch 430 and holds the clutch disengaged from the motordrive.

To permit operation of the setting clutch by any one of severaloperation control mechanisms, a depressible operating bar 503 isprovided which is supported by' a parallel link arrangement comprising alever 504 pivoted to the machine frame at 508 and a plate 505 pivoted tothe frame at 001. A spring 5I0 tensioned between the machine frameworkand the lever 504 normally maintains the bar in its illustrated raisedposition. A bell crank 5|! pivoted to the plate 505 at MS is normallyheld by means of a tension spring SIB, extending between the bell crankill and the bar 503, in a position wherein a notch formed on the lowerend thereof embraces an ear 5l5 on the clutch dog 394 so that upondepression 0! the bar 503 the bell crank 512 will rock the dog 394 outof the engaged notch of the setting clutch 430 causing the clutch torotate the setting shaft 431.

Mechanism (not shown) is provided to release the crank 5I2 from the ear5I5 during the first thereto and overlying the clutch dog 394 so as tobe rocked thereby.

M ain clutch control The main clutch 428 (Figure 3) is normally helddisengaged by a clutch dog 390 pivoted on a shaft III and urged intocontact with one of a plurality of diametrically opposed notches in theclutch by a spring II! tensioned between the machine frame and a togglelinkage N0 connectedtothe clutch dog 385.

To effect engagement of the main clutch under control of the settingclutch a cam 141 is keyed on the setting shaft 43I and engages a camfollower roller 145 mounted on a lever I48 pl oted on a shaft SM andspring urged into engagement with the cam. An interponent 603 ispivotally mounted at 004 on the lever I46 and is normally held in theposition illustrated in Figure 3 by a tension spring 6I3 extendingbetween ears formed on the interponent and the lever I40, respectively.The interponent 603 has a tip Blli which is adapted to engage a notch I0on the main clutch dog 395 and thereby, when the shaft 43I is rotated,rock the dog 395 out from whichever notch in the main clutch 420 it wasseated and thereby cause the main clutch to transmit rotation from themotor drive to the actuator mechanism including the gears I89 (Figure6).

To provide for continued multicyclic operation of the main'clutch incertain calculations, 4

as for example division, a latch 632 (Figure 3) is provided which ispinned to a rockable shaft 020 and urged clockwise by spring I533 intoengagement with an ear 020 on the clutch dog 3". When the clutch dog 335is rocked clockwise in division and other calculation operations aroller 034 mounted on the upper end of the latch "2 moves into latchingengagement with the under edge of ear 020 and thereby holds the mainclutch dog 3" from moving into eneasement with the main clutch 420.

Themainclutchdoglflalsomaintainsthe motor circuit completed duringoperation of the main clutch 426. Upon rocking of the dog 395 to effectengagement of the main clutch an extension 406 thereon (Figure engagesan ear 401 on the aforementioned lever 396 to rock this lever clockwiseand thereby close the motor-circuit.

Dipping o] accumulator register Upon rotation of the setting shaft "Iand in advance of actuation by the main clutch 426, the variousaccumulator drive gears 21! (Figure 6) carried'by the shiftable carriage250 (Figure l) are enmeshed with the aligned actuator drive gears I69,described hereinbefore, this being accomplished by cams, one of which isshown at 514, keyed on the setting shaft 43 l The various sets of gears211 and 213, as well as other elements (not shown) of the accumulatorregister, are carried on a series of plates 266 all pivoted by meansofarod 262 to the 'main' body of tlie carriage and all are connected attheir rightmost ends, as viewed in Figure 6, to a common bail 269.

The means for raising and lowering the .bail 269 to effect engagementand disengagement of the various gears 2H and I69 comprises a pair oflinks, one of which is shown at 566, slidable over pins 561 on spacedframe plates of the machine. Each link is provided with rollers 566engaging the bail 269 on opposite sides thereof and is urged upwardly bya spring 559 tensioned between the links and a pin on the machine frame.The links 566 are pivoted to cam follow'erlevers 510 rockable on a shaft225, the levers- 510 having rollers 513 engaging the cams 514 so thatupon rotation of the shaft "I, the followers 510 and links 566 are.moved to positively pull down the bail 269 against the action of thesprings 569. g

Means are provided to latch the accumulator register in its lowerposition during actuation. This means includes latch levers 515 pivotedat 516 to the machine frame and urged by springs 519 into latchingengagement with ears 516 on the cam follower levers 510. When thevarious plates 266 and the mechanism carried thereby are dipped the ears513 ride over the noses 511 of the latch levers 515 and arelatchedtherebeneath, thus retaining the gears 21! in mesh with the actuatorgears I99 until termination of operation of the main clutch at whichtime the latches 515 will be released as will be described presently.

Referring to Figures 6 and '1, the means for releasing the latches 515comprise levers 539 pinned on a rockable shaft coaxial with a shaft-58l. On one of the levers 539 is a stud 536 engaged by an arm 560 pinnedto shaft 58l. Also pinned to shaft I is an arm 564 engaged by an ear 592on an arm 59| pivotally supported on a shaft 590 and provided with anextension adapted to be engaged by a roller 593 carried by a supportingdisc 100A which is fixed to a sleeve 594 rotatably mounted on a shaft649. 594 is driven by a separate clutch which is operated as an incidentto termination of main clutch operations and is known as the "restoreclutch."

Restore clutch When the main clutch dog 335 is moved to stop anddisengage the main clutch 426 (Figures 4 and This sleeve roller 593rocks the lever 591 clockwise to rock the lever 564 and so rock lever580, which engages the pin 536 on the juxtaposed lever 539. Lateralexsition.

The sleeve 594 of the restore clutch 100 carries a cam 596 (Figure 6)which is employed to prevent the carriage from rising too rapidly underthe action of the springs 569 whenever the latches 515 are released. Thecam596 is engaged by a cam follower'lever 591 fixed to a rockable shaft-600. A pair of arms'599 also fixed t0 the Shaft 600 are joined by pinand slot connections 602 to the links 566 so that the rate of rise ofthe accumulator register under the pull of springs 569 is no greaterthan that permitted by rotation of the cam 596. r

The restore clutch 100 (Figures 4 and 6), besides effecting release ofthe carriage latch levers 515 and controlling the rate of return of thebail 269 and parts of the accumulator register to their upper positionsalso conditions certain of the divisioncontrol mechanism, as will appearhereinafter, under the section entitled "Division contro The restoreclutch is jointly controlled by the accumulator register dippingmechanism and by the main clutch dog in such a way that when- I ever theaccumulator register is in its lowe position-and the main clutch dog 395is seated in a notch of the main clutch, the restore clutch will engageand complete one cycle of operation.

The restore clutch is similar in internal construction to that disclosedin the patent to Friden Number 1,643,710, issued Septembe 27, 1927, andis directly controlled by an extending nose 102 (Figure 4) on a clutchrelease dog in the form of a bell crank 405 which is freely supported onthe shaft 600. An M-shaped lever 103 is provided to control the clutchrelease dog 405 and h s one foot thereof pivotally mounted in the shaft600. A short arm 104 extending from the lever 103 is provided with atenon on which is positioned a compression spring 105 extending betweenthe arm 104 and a tenon on the left arm of the clutch release dog 405. v

1 An arm 122 keyed to the shaft 600, and thus rocked counter-clockwiseby dipping movement of the accumulator, is connected to the M-shaped 5)the restore clutch-100 (Figures 4 and 6). to be 1 lever 103 by acombined compression-expansion link unit 123, as disclosed in detail inthe above mentioned Avery Patent 2,216,659. The link unit 123 iscomposed of a pair of links 11 5 and 116, the former pivoted at one endthereof on a stud mounted on the arm 122 and the latter link1l6 pivotedat one end thereof on a stud extending from the lever 103. The two linksslide relative to each other and have elongated slots at the free endsthereof each slidable over the pivotal stud for the other link. Acompression spring 1 is inserted in a pair of coextensive aperturesformed in the two links, being positioned over opposed tenons' extendingfrom each link, and thereby to the machine frame and urgedcounter-clockwise by a spring 1" tensioned between the latch lever andthe machine frame. The latch 10! is therefore rocked counter-clockwiseand an ear H8 thereon is rocked into a notch H9 formed in the M-shapedmember 103 to prevent coimterclockwise movement of lever 103 until themain clutch has been disengaged by reseating of its dog 385 in one ofthe full cycle notches of the clutch 428. The lowering of theaccumulator register mechanism (Figure 6), however, tends to engage therestore clutch even before th main clutch engages'and a secondrestraining means is provided to prevent this operation.

The left foot of the lever T03 is provided with a shelf I20 overlyingone end of a bell crank l2l, pivoted on the shaft 6| l, and having aroller 10! at the other end thereof in engagement with a cam 108 keyedon the setting shaft 431. On rotation of the setting clutch, therefore,the bell crank 12! is rocked to raise the lever I03 and thus insure thatthe ear I I8 of the latch member 10! will be able to engage the notch H9properly when the main clutch is engaged. As the setting clutchcontinues through a single cycle of operation the cams 514 (Figure 6)effect dipping of the accumulator register mechanism and, consequently,the shaft 500 is rocked counter-clockwise. Iherefore, the arm 122(Figure 4) keyed to the shaft R is lowered and the link unit 123 islengthened against the opposition of its spring H4. The parts remain sopositioned with the spring "4 compressed until the main clutch dog 395is permitted to reseat in a notch of the clutch 428 whereupon theextension 408 thereon strikes the ear N0 of the latch lever 10!, rockingit clockwise and removing its lug H0 from the notch H9 of the lever 103.Spring H4 then expands shortening the link unit 123 and rocking themember 103 counter-clockwise to carry the left leg (Figure 4) of lever103 down against the leftwardly extending arm .of the bell crank 405 torock this lever counter-clockwise and remove the nose lflzthereon fromengagement with the restore clutch 100, thereby enabling the clutch tobecome engaged.

Operation of the restore clutch, thus initiated, causes the latches 515(Figure 6) to be released in the manner described in connection withFig- 'uresfiand'landcontrolstherateofriseofthe links 568 through the cam596, as previously described, enabling the springs 56! to rock the shaft600 and arm 122 (Figure 4). This movement of arm '22 tends to compressthe spring H4 which, being stronger than the spring I05, transmits arocking movement to the link I13 and lever 103 to compress the spring105 until the nose 102 of the restore clutch dog 405 can reenter into anaperture of the housing of the restore clutch I00, whereupon the restoreclutch becomes disengaged and the mechanisms are brought to rest in theposition illustrated in Figure 4.

The restore clutch dog 405, when moved counter-clockwise to effectengagement of the restore clutch I00, causes the motor circuit to beclosed. This is accomplished by the leftwardly extending arm of the dog405 (see Figures 4 and- Division control As disclosed in detail in theabove mentioned Avery Patent2,216.659, division is performed by settingup the dividend in the accumulator register ill, as by the usual addingoperation, and

then setting up the divisor in the keyboard, and depressing the divisioninitiating key 910 (Figures. 1, 9 and 11). The machine thereupon carriesout automatically the operation of dividing the divisor into thedividend and registering the quotient in the counter register I800carried by the ,shiftable carriage 250. The operation consists ofsuccessive subtractions of the divisor from those digits of the'dividendwhich are re istered in orders of the carriage aligned with the portionof the selecting mechanism containing the divisor, and which may becalled the effective dividend." The machine continues to subtract untilthe'remainder in the effective dividend portion of the accumulator isreduced to a value substantially less than half the divisor whereuponthe division control mechanism is.

automatically tripped for stopp the subtraction. Since the machine isarranged to stop actuation only in full cycle position it proceedsthrough whatever fraction of a cycle may be necessary, after trip-oil,in order to complete the particular cycle of negative actuation then inprocess, which causes the machine to subtract a corresponding fractionof the divisor (which fraction may be any amount up to the wholedivisor) from the amount of the dividend re? mainder at the time oftrip-off. Since that amount was at the time of trip oif substantiallyless than the divisor, the remainder at the end of this negative cyclemay be either more or less than zero depending on whether the trip-offoccurred early or late in the cycle of subtraction. If the remainder isless than zero the machine will, of course, be in an overdraftedcondition. Means are provided to sense the condition of the machine atthis time and if it is in an overdrafted condition the sensing meanswillautomatically cause a subsequent plus actuation cycle to be institutedto correct the overdrafted condition after which the carriage isautomatically shifted one step to the left. However, if the remainderhas not been reduced to less than zero at the end of the cycle thesensing mechanism will not effect the corrective" plus actuation cyclebut the carriage will, nevertheless, be shifted one step to the left.

As the carriage is automatically shifted to the left, additionaldividend digits in the accumulator register are successively broughtinto alignment with the part of the actuator mechanism controlled by theportion of the keyboard upon which the divisor is set until the carriagereaches its leftmost position. Since the construction and operation ofthe division control mechanism is described in detail in-the above AveryPatent Number 2,216,659, only a brief description of the mechanism willbe given herein.

The division initiating key 910 (Figure 11) is mounted on a key stem 9'"supported by a pair of parallel levers!" and 913 pivotally mounted onthe machine frame. A roller 814 on the bottom end of the key stem 9Hnormally lies in front of a division control member 515 (see Figure 9).The member 915 is pivotally mounted on a shaft 918 and is urgedclockwise by a. strong spring 8llv the top of the member 915 strikes theupper edge The division key 910 is held in depressed position by a latch902 (Figure 11) pivotally mounted on a shaft 1222 and provided with anotch 981 which when the key 910 is depressed is moved into latchingengagement with an ear 960 of lever 913 by a spring 983 tensionedbetween an arm of the latch 982 and a pin on the frame.

Means are also provided for insuring that if the division key 910 isdepressed sufllciently to release the member 915 (Figure 9) it willautomatically be depressed a sufllcient additional distance to permitnotch 901 (Figure 11) to engage ear 980 even though fingerpressure isremoved from the key as soon as member 915 is released. For this purposemember 915 (Figures 8 and 9) carries a member 1111 provided with an edge1119 engageable with roller 91 1 which edge extends along a linedisposed at anobtuse angle with respect to a radius extending from shaft916 as a center and therefore acts, during clockwise movement of member915, as a cam engaging roller 914 to effect additional downward movementof key 910.

During the operation of the machine, as appears hereinafter, latch 982is released from ear 980 before member 915 has been completely restoredto its normal position in which it is shown in Figure 9, and in order toprevent member 1111 from holding key 910 depressed so far as to permitre-engagement of latch 982 with ear 900 after such release, the leftmostend of edge 1119 of member 1111 is spaced from the member 915suiliciently to permit roller 914 to move upwardly upon release of latch982 far enough to prevent reengagement of the notch 981 with ear 980.Also, the member 1111 is movably mounted on member 915 by meanscomprising pins 1115 on member 915 extending through arcuate slots 1116in member 1111, so that during counterclockwise movement of member 915member 1111 will not cam the roller 914 downwardly but will be movedrightwardly and upwardly with respect to member 915 by said rollerovercoming spring 1118 which normally holds member 1111 in the positionshown, and roller 914 will be guided by the arcuate lower edge 918 ofmember 915, which edge conforms to an arc described upon a unifo radiusabout shaft 916. a

The first setting clutch cycle initiated by depression of the divisionkey will cause retraction of the main clutch dog 395 (Figure 3) and thespring 633 (Figure 3) will become active to hold the latch 632 inlatching engagement with the main clutch dog 395 whereupon multicyclicoperation of the main clutch ensues. The actuator mechanism, includingthe gears 189 (Figure 6) are conditioned to operate in a subtractivedirection, as described in the aforesaid Avery patent, by the depressionof the division key 910 so that the divisor set up on the keyboard willbe subtracted one or more times from the dividend appearing in theaccumulator register.

Sensing mechanism is continuously effective throughout the series ofsubtractive operations effected in each shifted position of the carriageto compare the continuously changing remainder with the divisor and tooperate the automatic controls for terminating the subtractiveoperations when thatremainder becomes substantially less than thedivisor. This-same sensing mechanism is subsequently employed in eachcarriage position to ascertain whether or not an overdraft has occurred.The sensing mechanism comprises a sensing lever 901 under control ofeach order of the keyboard (plus two additional levers located one andtwo orders to the left, respectively) each of which levers is arrangedto cooperate with related mechanism positioned by the correspondingaccumulator dial, but only the sensing lever controlled by the key boardorder which contains the highest significant digit of the divisor, andall sensing levers to the left thereof are permitted to come intooperation. Means (not shown) is provided to hold the various sensinglevers to the right of the said sensing lever out of controllingposition. The orders in which the sensing lovers are thus permitted tocome into operation will be referred to as the controlling orders."

As more fully described in the aforesaid Avery patent, during rotationof the active accumulator register dials 219 (Figure 9) a snail cam 281connected to each of the dials will be rotated in a clockwise direction,and cam follower 315 pivoted on rod 212 and following its respective cam281 by means of a roller 316 will depress a shelf formed on sensinglever 901 pivotally supported at 902, thus rocking the lever 901clockwise. A foot 906 on one or more of the levers 901 is normallyengaged during division by a division control bail 901 pivoted at 942 tothe machine frame and urged clockwise by a-spring 944 tensioned betweenthe machine frame and an arm on the bail 901. A link 2115 is connectedbetween an arm on the,bail 901 and a lever 2118 pivoted at 2119 to themachine frame. The lever 2118 is connected through a pin and slotconnection to an arm 2120 pinned on a shaft 2121.

Referring to Figure 3, a bell crank 2013, also pinned on the shaft 2121,has a leftwardly extending arm underlying an ear 2124 of the main clutchdog latch 632, so asto engage and rock the latch 632 out from under theear 020 of main clutch dog 396 upon tripping of the bail 901 by thesensing levers 901.

The position of the pivot 902 (Figure 9) of each of the controllingsensing levers 901 is controlled by the size of the digits in thecontrolling keyboard orders containing the divisor, as disclosed indetail in the above mentioned Avery Patent Number 2,216,659. That is,the position of each pivot 902 in the controlling orders is 5 adjustedin a substantially vertical direction by an amount dependent upon thevalueof the divisor as set in the corresponding keyboard order, thisannunt being such that when the remainder in the accumulator dials isreduced to approximately one-half of the divisor, the cam 281 in thecontrolling order of the accumulator will have forced its cam follower315 and, consequently the corresponding sensing lever 901, to a positionwherein the foot 906 on the sensing lever 901 passes above therightwardly extending finger of the bail 901, permitting the spring 944to rock the bail 901 clockwise and effect release of the latch 632(Figure 3) so as to stop the main clutch.

It will be recalled that the main clutch dog 395 (Figures 4 and 5), whenrocked home by its spring 612, will trip the latch 101 and allow the nowextended link unit 123 to contract and rock the lover 103 and therestore clutch dog 405 counter-clockwise to cause engagement of therestore clutch 100.

During the restore clutch cycle and whil the accumulator register isbeing raised, a link 040 (Figure 9) is moved to the left by a cam 040driven by the restore clutch 100. A lever 041 pivoted on the shaft 010and pivotally connected to the link 840 is rocked counter-clockwise.This lever 04'! has a notched bell crank I042 pivotally mounted thereonand adapted to engage an ear i021 extending from the division controlmemher 015 so as to-rock the member slightly further counter-clockwisethan is illustrated in Figures 8 and 9 wherein it may be latched by alatch 050 to be described hereinafter. A second bell crank I044, freelymounted on the shaft 015,,has one end thereof provided with an elongatedslot embracing a pin I040 on the bell crank I042. A spring I045tensioned between the other end of the bell crank I044 and the frameholds the bell crank 1042 in position to engage the extension 1021during theflrst part of the movement of the cam 049, providing thedivision control member 915 has been rocked clockwise of its illustratedposition by spring 911 wherein the car 1021 is located at "21a, butcauses the bell crank I042 to be rocked counter-clockwise relative tothe lever 041 upon continued movement of the cam 040, if the member 015is maintained in its illustrated position, so as to underride and missthe ear I021. Thus, since the member 015 is in its clockwise rockedposition during the repeated subtraction of the divisor from thedividend, the bell crank I042 will engage the extension I021 and willrock the member 015-counter-clockwise until an ear I052 thereof islatched by a latchlever I050 (Figure 8) which is pivoted at the left endthereof (in a manner not shown) to the machine frame and spring presseddownwardly.

The division control member 015 is pivotally connected at I065 to a linkI054 (Figures 2A, 8 and 9) urged counter-clockwise relative to themember 015 by a tension spring I054a extendins between the link and themember. Link I054 has a shoulder I055 adapted to engage an ear I055 on abell crank I051 pivoted on a pinand normally held in its illustratedposition by a tension spring I004 extending between the bell crank andthe machine frame. An ear I050 (see also Figure 2) on the bell cranki051 overlies the setting clutch operating bar 500.

When the member 015 is first rocked clockwise upon depression of thedivision key 010, the link I054 is carried rightward thereby to allowthe shoulder I055 to drop to a position behind the ear I050 on th bellcrank I051. Now, upon the succeeding restore clutch cycle, the cam 040'(Flaure 9) causes the member 015 to be rocked countor-clockwise, asdescribed above. During this rocking of the member 015 the shoulder I055of the link I054 engages the ear I050 to rock the bell crank I051clockwise against the action of the spring I004, causing the ear I050 todep the setting clutch operating bar 000 (Figure 2) and initiatea.corrective cycle as described in detail in the above mentioned AveryPatent Number 2,216,659, to correct for an overstroke if such hasoccurred. Means (not shown) are provided to release the link I054 fromengagement with the ear I050 of the bell crank I051 during thesucceeding setting clutch cycle so as to allow the parts to return totheir illustrated position.

Operation of the restore clutch 100 (Figure 9), furthermore, returns thedivision control bail 001 slightly to the an of the position illustratedin Figure 9 so that it may be relatched by the various blocking tails000 of the sensing levers if an overdraft has occurred. Since theblocking tails 006 had been raised clear of division control bail 001 inall controlling orders of the machine at the time the hall was releasedto terminate negative operation (due to the remainder then beingsubstantially less than the divisor), and since the only change-in dialregistration subsequent to trip-off has been a further subtraction of afractional part of the divisor. the remainder will now either be stillless than it was at time of trip-off (in which case blocking tails 000will be raised even further clear of bail 001 and the bail will be freeto be again rocked clockwise through its complete path of movement bythe spring 044 to prevent a subsequent corrective" plus cycle ofactuation, as will be described presently) or an overdraft will haveoccurred bringing the higher order dials to register 9'5" which beinggreater than the 0" divisor settings effective above the highest orderof the divisor will cause the blocking tails 000 to block bail 001.

For the purpose of returning the division control bail 001counterclockwise, the link 040 is provided with an extension I050adapted, on leftward movement of the link, to rock an arm I00l pinned onthe shaft IIZI to which is also pinned the arm 2I20 (Figure 9), therebycausing the members 2H0 and 1H5 torock the bail 001 counter-clockwise.As positioned at the end of the restore cycle, the cam 040 is soproportioned as to permit the link 045 to be spring returned toward theright, as viewed in Figure 9, and if the bail 001 is not held at thistime by any of the locking tails 000 it will be allowed torockoompletely through its path of movement under the urge of the spring004 and thus cause the bell crank 2013 (Figure 3) to engage the lug 005on the interponent 500 and rock the same downward with respect to thecam follower lever 140 so that, during the succeeding second settingclutch cycle in which the follower 145 is rocked by the cam 141, themember 000 will not engage the main clutch dog 005 and main clutchoperation will not occur. If, however, the bail 001 is blocked by ablocking tall 000 the bell crank 2010 will notbecome effective to rockthe member 000 to an ineffective position and a main clutch operationwill therefore be instituted, means (not shown) being provided to limitthe main clutch operationtoonecycleandtoinsurethattheactuator is drivenin a plus direction. It will thus be seen that main clutch operation atthis time depends on whether or not an overdraft has occurred, for if anoverdraft has taken place it is necessary that a corrective-main clutchcycle be instituted.

In view of the fact that the reversing device for controlling thedirection of operation of the actuator, as well as the controls thereforare disclosed in detail in the above mentioned Aver! Patent Number2,216,659, such is not disclosed herein. However, it should be notedthat the reversing device is set to cause the actuator to operate in asubtractive direction upon clockwise rocking of the member 015 at theinitiation of the division operation by the roller 010 thereon Duringthe first restore clutch cycle the member 015 is returnedcounter-clockwise and the link I054 (Figure 2A) thereon rocks bell crankI001 .asabovedescribed. Asthebellcrank I051rocks to cause of the settinclutch for a posslbloconectlnncyclearaler I000onthebell crank sets thereversing device to cause the actuator to operate in a positivedirection ,in the event a main clutch cycle is instituted.

If a corrective cycle has been initiated the main clutch dog will arrestthe operation of the main clutch after a single cycle of operation andwill automatically institute a second restore clutch operation in theusual manner. If, however, such a corrective cycle is not initiated, thesecond restore clutch operation will be automatically instituted towardthe end of the second setting clutch cycle which, it will be recalled,was instituted by recocking of the division control memher 915 (Figure9). Since in the latter circumstances the main clutch dog 385 is notremoved from the position in which it is shown in Figure 4, itsextension 408 prevents any engagement of the member mi in the notch 1I8of the M-shaped member 103 controlling operation of the restore clutch,and as the accumulator mechanism is dipped to rock the shaft 600counter-clockwise, engagement of'the restore clutch is prevented only bythe bell crank 12I which engages the ear 120 on the member 103. As thesetting clutch cycle draws to a close, the cam 108 permits the bellcrank 12I to recede from the car 120, permitting the tension link unit123 to cause engagement of the restore clutch.

The second restore clutch operation controls the raising of theaccumulator mechanism, as described hereinbefore, and initiates anautomatic carriage shifting operation as will be described presently.During this second restore clutch cycle, the member 815 will have beenheld substantially in its illustrated position by the latch I050 (Figure8) and consequently the extension I021 thereof will not be engaged bythe latch I042. It should be noted that the division key 810 (Figure 11)is maintained in a depressed position throughout the division operationby the latch 982 and will, therefore, not interfere with the subsequentclockwise rocking movement of the division control member 815 in thenext carriage order unless the carriage has reached its left endposition or a special stop key 985 (Figures 1 and has been depressed.

Carriage shift control in division A complete disclosure of the carriageshifting mechanism and controls thereof will be found in theaforementioned Avery patent, but the operation thereof will be brieflyoutlined herein in connection with the division mechanism.

Shifting of the carriage to the right or to the left is effected undermotor power by a train of elements (not shown) including a shaft I33I(Figure 8) which is rotatable one-half a revolution for each cycle ofoperation of the carriage shifting mechanism. Control means are providedfor causing a leftward shift of the carriage in division and comprisesan ear I384 (Figure 8) which when moved to the left institutes aleftward shift in a manner not shown. This car is adapted to be engagedby a hook formed on a floating dog I383 pivoted on a lever I380 which ispivoted on a shaft I316. When the division key 818 (Figure 9) isdepressed, an ear 91'Ia on the stem 81I thereof engages the leftmost endof the dog I383 and rocks the same counter-clockwise until it hooks. theear I384.

A floating shift control lever I311 is pivoted at I318 to the lever I380and the leftmost end thereof, as viewed in Figure 8, is weighted so thatit tends to rock counter-clockwise aboutits pivot At the end of adivision operation in a particular carriage position, the floatingcarriage shift control lever I311 is moved to the left, as viewed inFigures 6 and 8, to initiate a carriage shift to the left. During thedivision operation in a certain carriage position an ear I386 on one ofthe cam followers 510 is moved to the right of its position illustratedin Figures 6 and 8 by virtue of the dipping movement imparted to thelinks 586 by the cam followers 510 when rocked by the cams 518 so thatthe weighted left end of the lever I311 will rock the levercounter-clockwise until the notch I380 on the right hand edge thereofembraces the ear I386. Now, as the final second restore clutch cycle inthe current carriage order ensues, enabling the springs 569 to lift thelinks 566 and rock the cam followers 510 counter-clockwise, the floatinglever I311 is shifted to the left by the ear I386 and the dog I383 islikewise shifted to the left through the action of the lever I380. Sincethe dog I383 is at this time hooked over the ear I384, the same will bemoved to the left to institute a leftward shift of the carriage.

It should be understood that the above carriage shifting operation takesplace at the end of the final, or second, restore clutch operation ineach carriage position following the corrective cycle instead of at theend of the first restore clutch operation. The carriage shift isprevented from taking place at the end of the first restore clutch cycleby reason of the fact that the division control member 915 is allowed tobe held in a clockwise position by its spring 811 during the negativecycling of the actuator, in which case a roller mounted on the ivot pinI065 engages the under 1 surface I318 of the shift control lever I311 tohold the same rocked to position the notch I380 thereof below the pathof movement of the ear I386 until after the restore clutch has operatedsufilciently to allow the cam follower lever 510 to be rockedcounter-clockwise and thereby move the-ear I386 to substantially itsillustrated position wherein it cannot engage the notch I380 and shiftthe floating lever I311. I During the final restore clutch cyclefollowing the corrective cycle, however. the division control member815, being latched in its counter-clockwise rocked position by the latchI050, is ineffective to prevent initiation of the carriage shift.

During the initial shift cycle one of a pair of rollers I363 (Figure 8)placed diametrically opposite each other on a disc I362, which isrotated by the shaft I33I, rocks a lever I355 pivoted to the frame studI35I against the action of a spring I358, and a pin I356 on this leverengages and rocks a bell crank I381 pivoted to the machine frame atI388. A shelf I388 extending from the bell crank underlies the latchI050 and the leftmost end of the lever I311 so that the lever I311 willbe rocked from engagement with the ear I386 to limit the shift operationto one step and the division control member 915 will be released by thelatch I 050 to initiate the division operation in the new car carriageorder.

Termination of operation in division The above repetitive tour ofoperations is repeated in each successive carriage position until thecarriage reaches its leftmost position or the stop key 985 (Figures 1and 18) is depressed, when further operation of the carriage shiftingmechanism is prevented and the machine is brought to a standstill. Asthe'carriage moves into its leftmost position, a projection I510'(Figure 11) carried by the right hand carriage plate 25l strikes theunder surface of an inclined cam way i!" formed on a lever 1512 so as torock the lever counterclockwise against the action of a tension springliliextending between the lever 1512 and the machine frame.

During a division operation, with the carriage in its leftmost position,the division key will be released from the restraint of latch 882(Figure 11 A leftwardly extending arm of the lever i512 underlies an car1867 on the upper end of a bell crank it pivoted at MS! to the divisionkey latch 882. When the lever I572 is rocked coonter-elockwise by thecarriage, the bell crank I068 is rocked by a spring extending betweenthe bell crank and part of the division key latch 88: to hook a leftwardextension thereof around the car 1058 of the bell crank I051 (Figure2A). This hell crank, it will be recalled, is rocked by the link 5854,connected to the division control member "5, during the first restorecycle in each order for the purpose of initiating a corrective cycle. behooked over the extension 1056 during such rocking, the bell crank "58will be pulled to the left during the first restore cycle rocking thelatch lever 882 counter-clockwise about its supporting shaft 1222 torelease the lateral extension 980 of the lever 913. Now, the divisionkey rises sumcientiy to prevent reengagement of the notch "I of latch982 with car 880 of lever 913, but is prevented from moving to raisedposition, in the specific embodiment herein described, by a supplementallatch hereinafter described.

During the succeeding second setting clutch cycle this supplementaldivision key latch, which is provided for the primary purpose ofperforming certain functions related to the counter reverse control andis therefore described in connection therewith in this specification, isreleased and the division key 918 is returned to raised positionbringing its roller 914 in front of member 915 to prevent resumption ofsubtractive operation. Thus'the machine is brought to rest at theconclusion of a restore clutch cycle following the second setting clutchcycle, with or without an intervening corrective addition cycle of theactuator as previously described,

A division operation may be terminated at the conclusion of operation inany carriage position by a single depression of the stop key 985(Figures 1 and 10) leaving a quotient digit in that order accuratelyregistered, or it may be terminated at once by two successivedepressions of the same key which may possibly leave an inaccuratequotient digit in the counter. The stop key "5 is slidably supportedupon pins extending from the machine frame and is provided with anoffset 9" which overlies a lever pivoted to the frame and connected by apin and slot connection with a. lever IIII pivoted on a shaft Ill" andconnected by means of a. sleeve Illa (Figure 11) with a bell crank it"which is normally urged in a clockwise direction by a tension spring ll"extending between the bell crank I0" and the machine frame. Upondepression of the stop key Q the bell crank III! is rocked in acounterclockwise direction and a link I019 pivotally connected theretoand normally urged upwardly bya spring ll", extending between a pin onthe machine frame and the link M19, is moved to the right. The link "19carries a shelf I084 engageable with a tall I." of the division keylatch I82 and is limited in its upward travel under tension of spring I.by an ear llll formed on If the end of the bell crank I068 a lever II".The never I." is pivoted on the shaft I222 which carries the divlson keylatch 982, and has but a limited swinging movement relative to thislatch so that for the present purposeltmaybeconsideredasanintegralpartofthe latch. Upon depression of the stop key "I the link Ill! is moved tothe right carrying it: shelf l0" against the lower end of the tall ll"of the division key latch 882. This swings the division key latch 982counter-clockwise releasing the division key to rise slightly until heldby aforesaid supplemental latch (Figure 12) Thus, the division key willbe permitted to rise during the second setting clutch cycle in thatorder in the same manner as described before.

A second depression of the stop key after the latch 982 has been trippedalso moves the link ill! to the right. It will be recalled, however,that upon the first depression of the stop key the latch 982 was movedin a counter-clockwise direction. Thus, the lever Ill! was swung up-.wardly and its ear ll" permitted the link II" to rise under the actionof its spring ID". This rise of the link [I19 is suihclent to cause itsright hand end to engage an ear M2 on an extension of a lever 2H1 fixedto the shaft 26 upon the second depression of stop key I". Referring toFigure 3, it will be recalled that the latch $32 is also fixed to theshaft '20 so that movement of this shaft by the link I." will cffectrelease of the main clutch dog I! and thus immediately arrest operationof the main clutch, and a restore clutch operation will ensue followedby the usual second setting cycle during which time the division key iscaused to rise in the some manner as described hereinbefore.

Control of counter mechanism in division The machine of the presentinvention has a counter register ll carried by the carriage (Pigures 1and 12) to serve as a multiplier register in multiplication operationsand a quotient register in division operations. The counter actuator isconnected through a reversing mechanism with the main clutch whereby thecharacter of the count registered bythe counter may be selectivelycontrolled.

Included in the drive for the counter achmtor is a double integral idlerI492 (Figure 14) sultably driven in time with the main clutch 42'. Theidler "I is directly meshed with a gear Ill journaled on a slotted shaftIII. while the idler 492 is entrained through an idler 1m with a secondgear Illl journaled on the shaft llll. The gears Ill. and I'll form areversing mechanism, one being driven in a direction opptflte thatoftheother andeachbeingadamdtobc selectively keyed to, the shaft III! todrive the same in either of opposite directions.

A gear "2|, keyed on the shaft llll, meshes with a gear "22 fixed on ashaft "23 which carries an eccentric I! (Figure 12). A lever mo (Figures12 and 14) forming part of the counter actuator is iournaled at itslower end on theeccentric "II and has an irregularslot guidedover aframe pin ll". Pivoted to the upper end of the lever III. is an actuatorfinger I824 having a slot therein guided over a frame 11h I838. Diefinger I824 has a tooth cngageable with a gear I". entrained through anidle:- I!" with a dill gear I"! for driving an associated ommtcr dialI815, the latter being connected to the gear llll through a planetarygear arnngemcntnotshown. Thearrangemmtofthecmmtcrnngcr mum theleverllillssucbthsttorcochqclootopuation of the main clutch the tooth oifinger I824 will engage between the teeth of the gear I880 and advancethe same an increment of one tooth pitch-in one direction or anotherdepending upon which of the driven gears I8I8 and I8I8 is keyed to theshaft I8I9, thus advancing the associated dial one unit of registration.

For the purpose of selectively keying one or another of the gears I8I8and IBM! to the shaft I8I9 a key I8I2 is slldable in the longitudinalslot in shaft I8I9 and has a tooth I8I4 engageable in slots I8I1 formedin the juxtaposed hubs of gears I8I8 and I8I8. The key I8I2 is rotatablyconnected to a shaft I8I0 slidable in a bearing I8 and having a notchformed therein and embracing a cam I808 having two spaced c'ammingi'aces I825 aligned in a single plane and a third camming face I828displaced in a second plane. The

cam I808 is pivoted on a pin I808 and is con nected by means of a linkI801 with a diiferentially settable link I813, the link I801 beingconnected to a stud I849 located on the link I813 midway between itsends. The lower end of this difierential link I813 is pivoted to an armI805 free on the shaft 918 while the upper end of the link is connectedto a settable member I803 through a connecting link I812. The memberI803 has a portion extending through a slot in the keyboard whereby itmay be selectively manipulated into either of two positions.

A spring pawl I831 is provided for pawllng the member I803 in either ofits manipulated positions and is pivoted at I838 and urged in aclockwise direction by spring I839. This pawl has a nose I810 engaging aprojection I81I on the lever position, illustrated in Figure 13, at thestart of the division calculation. v

According to the present invention this is accomplished by a lever I120(Figures 12 and 13) secured to the shaft 918, which shaft, as shown inFigure 11 is connected to the division key 910 by member I028 fixed tothe shaft 918, link 885 pivotally connected at one end to the memberI028 and lever 913 pivotally mounted on the machine frame and pivotallyconnected adjacent 15 Figure 11 and in Figures 12' and 13, carrying anear. I12I on the upper end 'of lever I120 into engagement with the leftedge of arm I805 and moving the latter from the positionin which it isshown in Figure 12 to the position in which it is shown in Figure 13.

Arm I805 being releasably retained by the spring pawl I142 which engagespin I143 on said arm, lever I120 may be returned to the position inwhich it is shown in Figure 12 without effecting any movement of armI805, and unless said arm is restored to thepositlon in which it isshown in Figure 12 by the restoringmechanism hereinafter described, itwill remain in the position in which it is shown in Figure 13 after thedivision an operation has terminated and the key 910 has been restoredto raised position. Under such circumstances, if the next calculation isa division operation no adjustment of arm I805 by lever I120 will takeplace, because the arm I805 will already occupy the positionin which itis shown I803 to retain it in either position in which it may I be set.

The arm I805 and the lower end of the link I813 are pawled in either oftwo positions by a spring pawl I142 pivoted on the frame pin I138 andprovided with a pair of spaced V-shaped notches, one of which is held inembracement with a pin I143 on the arm I805 by a spring I144 tensionedbetween the pawl and the frame.

I803, When this member is in its rearward illustrated position thecounting register will give a direct or positive count of multipliers inmultiplication and of quotients in division, while when member I803 ismoved to its forward position the counter register will give acomplementary or negative count oi. multipliers in multiplication and acomplementary count of quotients in division.

In order to obtain a true figure multiplier registration or true figureitem count in multiplication, additive, or subtractive operations it isnecessary that the counter dials be driven in the same direction as theaccumulator dials are driven, while to obtain a true figure registrationof quotients in division operations it is necessary that the counterdials be driven in the opposite direction to that in which theaccumulator dials are driven. This requires a reversal of the counterdrive upon initiation of the division operation so that in whicheverposition lever I803 stands, the interchange from the proper direction ofactuation of the counter register for multiplication, etc., to theproper direction of actuation thereof iordivision is secured. This isaccomplished by automatically shifting the pivotal connection of armI805 and the lower end of the link I813 to an alternate rearward inFigure 13. v

Independently actuated means are provided for restoring the counterreversing mechanism from its division setting to its normal setting,which 40 means is arranged to be disabled upon depression cording to thepreferred embodiment of the in- 13 to the position in which it is shownin Fig-- vention here disclosed, this restoration. is accomplished bymeans operated by the setting clutch which means are eifective torestore the arm I805 from the position in which it is shown in Figureure 12.

For this purpose member I122 (Figures 12 and 13) is pivotally mounted atI123 on a link I1I3 adapted to be reciprocated so as to produce agenerally horizontal movement of the pivot link I1I3 is pivotallyconnected to an arm "I4- I123. At its lower end, the link I1I3 ispivotally connected by a pin I124 to.an arm I125 pivot--- ally mountedon the frame of the machine at I128, while at its upper end (see Figure6) the fixed to shaft 800, which shaft as previously described. isrocked counter-clockwise during each cycle of operation of the settingclutch and clockwise during each operation of the restore clutch. Thiarrangement is such that during each setting clutch cycle member I122 ismoved leftwardly as viewed in Figures 12 and 13, while during eachrestore clutch cycle it is moved rightwardly. I

Member I122 is provided with a spring I128 tensioned between a tailthereof and an ear of a second pivotally mounted member I121,hereinafter described; which spring constrains member I122 to rockcounter-clockwise about its pivot I123 and maintain the upper fork ofits bifurcate left end in engagement with the upper side of the ear I12Iof lever I120. when lever I128 is in the position in which it is shownin Figure 12, which is when the division key 810 is raised, member I122is rocked by its spring I120 to its lowermost position, and a shoulderI145 thereon is positioned so that upon leftward movement of memberI122, which occurs during each setting clutch cycle, said shoulder willengage a pin I148 extending from arm I805 and restore arm I805 from theposition in which it is shown in Figure 13 to the position in which itis shown in Figare 12.

lifeans are provided, which are effective whenever the division key 910stands depressed, for disabling this restoring mechanism. The upper forkof the bifurcate left end of member i122 extends at such an angle withrespect to the path of movement of the ear I12I of lever 2120 thatclockwise movement of lever I120 from the position in which it is shownin Figure 12 to the position in which it is shown in Figure 13 willraise member I122 sufficiently so that the path of movement of theshoulder I145 during leftward movement of member I122 will be above thepin I146, and no setting clutch cycle occurring while the division key810 stands depressed can therefore effect restoration of the arm I805 tothe position in which it is shown in Figure In the particular machinedisclosed in the aforesaid Avery patent the latch 882 (Figure 11)hoiding the division key 818 depressed is released concurrently with theleftward movement of member 815 (Figure 9) prior to the last settingclutch cycle in terminating a. division operation.

Therefore it is necessary in applying the present invention to such amachine to provide a sup- -elemental latch for the member I120 (Figures22 and 131 which will hold the member I120 in position in which it isshown in Figure 13 u il the shoulder I145 of member I122 has sed overand beyond pin I148 during the ast setting clutch cycle, so that thecounter will not be restored from its division setting to its normalsetting and thus register erroneously wine the corrective addition cyclewhich will ow the last setting clutch cycle if the accuator regis rs anoverdraft. In applying the ention to a machine in which the divisionrating member not released or restored umil registration has beencompleted, however, wiii be apparent that no such supplemental lat-ch isrequired.

The supplemental latch of the present disclosure comprises a latchingtooth I128 on the upper for of member I122, which tooth is adapted toengage the ear I12I of lever I120 and hold the latter in the position inwhich it is shown in Figure 13. The latching tooth I128 is so positic-ned that when the division key 810 is held in depressed position by thelatch 082 (Figure 11) the ear I12I (Figure 13) is spaced rightwardlyfrom the tooth I128. Thus the release of latch 882 permits the key 810to rise a sufficient dis-- tance toprevent reengagement of latch 882,but latching tooth I128 arrests the accompanying counter-clockwisemovement of lever I120 so that shoulder I145 is not lowered a sufiicientdistance to eng e pin I148 during the ensuing setting clutch cycle.

Means are provided for releasing the supplemental latch I128 during thesaid last setting clutch cycle but only after the shoulder I145 ofmember I122 has passed above and beyond the pin I148 during the leftwardmovement of said member. For this purpose member I122 is provided with acam face I engageable with frame pin I188 during leftward movement ofthe member I122 but spaced therefrom a suflicient distance so thatupward movement of member I122 will be effected thereby to trip thelatch I128 only after the shoulder I has passed above and beyond theposition in which pin I148 is shown in Figure 13.

It should be noted that the cam face I140 Is proportioned so as to raisethe shoulder I145 completely out of engagement with pin I148 duringleftward movement of member I122 while lever I120 occupies the positionin which it is shown in Figure 12 just as pin I148 reaches the positionin which it is shown in that figure, but that even if variations withinordinary manufacturing tolerances result in the raising of shoulder I145out of engagement with pin I145 slightly before the pin reaches thatposition under such conditions, shoulder I145 will have moved pin I148at least far enough leftward so that the remainder of the leftwardrestoration of arm I005 will be eifected by the spring pawl I142 thedivergent notches of which engage the pin I148 on arm I805 and can thusserve to move it from lust past an intermediate position to a fullyrestored position and vice versa.

This arrangement is such that after a division calculation, if thesucceeding calculation is any other than a division cal ation theensuing preparatory setting clutch cycle will move the membq I122 to theleft and the shoulder I140 will engage the pin I148 to rock the arm I885and lower end of the link I818 leftward to their full line positionillustrated in Figure 12, thus returning the cam I808 to condition thecounter drive to cause a direct count of the machine cycles and thecentralizer I142 will become effective to hold the counter controllinkage in this position.

If the next calculation, however, is a division calculation the leverI120 will have been rocked back to the position illustrated in Figure13, raising the member I122 before the ensuing setting clutch cyclebecomes effective, and this will prevent the member I 122 from rockingthe arm I805 back to its normal forward setting.

It will be noted that the setting of the lever I808 will reversethecharacter of the count by alternatively'positioning the upper end ofthe link I813. That is, when lever I802 is set in a forward position andthe arm I805 and the lower end of the link I818 are in their forwardpositions illustrated in Figure 12, the cam I808 will normally be set inan intermediate position with the cam face I828 engaging the notch inshaft "II, the rightward setting of the arm I805 incidental todepression of the division key will result in the cam being rockedcounter-clockwise to engage the lower cam face I025 in the notch inshaft I8I8.

Means are provided to prevent inadvertent rcsetting of the lever I808during actuation. Located on the member I121 which is pivotaliy mountedon pin I188, is an ear I148 which, when the machine is at rest, liesdirectl behind a notch I150 in the spring pawl I881 thereby permittingthe lever I808 to be manipulated at will. However, during a calculationof any kind in which the accumulator register is dipped for actuation,the link I1I8 will be held in a leftward position and a roller I188onarm I128 will permit the spring I128 to rock-the member I121 slight yclockwise to position the ear I148 out of line with the notch I150 inthe spring pawl I031, thus preventing the pawl I031 from being rockedthrough the full extent of its stroke during attempted movement of thelever I 803 from one setting to the other and will thus prevent suchmovement.

Means are also provided for preventing depression of the division key910 after dipping of the carriage has occurred in response to theoperation of any other control key. For this purpose member I121 isprovided adjacent its left end with a notch I139 adapted to engage theright edge of the ear I12I of lever I120 when during the dipping of thecarriage the roller I130 moves from under cam I131 01' member I121,provided the division key has not previously been depressed.

The interlock I121 also serves to prevent depression of the division keyafter it has once been released during the second setting clutch cycleincident to termination of a division operation and before the machinehas come to a complete rest. During such a second setting clutch cyclein a terminal order in division, the lever I120 is Easy division keyoperation The present invention also contemplates the provision of meanswhereby the pressure which must be exerted by the operator upon thedivision key to initiate a division operation is minimized. This isaccomplished, in general. by automatically applying spring force toraise the division key at the time it is released from the last of thelatching means holding it depressed, and automatically relieving suchspring force at all times when manual depression of the key may takeplace. In a machine embodying this mechanism only sufficient springforce need be applied for normally maintaining the key in raisedposition, to prevent it from moving gravitation pressed position.

Such a very light spring is indicated at I155 (Figures 12 and 13) aseffective through lever I120, shaft 916 (see also Figure 11), memberI028, link 965, and lever 913 to normally maintain key 910 in raisedposition.

The means for automatically applyingspring It will be recalled that theshaft 600 is rocked counter-clockwise from the position in which it isshown in Figure 6 during each setting clutch cycle, and clockwise backto said position during each restore clutch cycle. Thus during eachsetting clutch cycle, if the lever I120 is in the position in which itis shown in Figure 13, spring 4130 will be tensioned to exert a springforce tending to rock lever I120 counter-clockwise and ally, or underthe influence of vibration, to dedepressed, but after the release oflatch 382 in the manner previously described in connection with thetermination of a. division operation, the

latch I129 becomes effective as the last latching means holding thedivision key depressed. Under such circumstances it will be evident fromthe above description that the spring means comprising spring I130 isunder tension at the time the latch I129 is released and that the springforce thereof is thereupon effective to raise the division key.

During the ensuing restore clutch cycle the shaft 600 is rocked back tothe position in which it is shown in Figure 6 relieving the tension onspring I130 leaving the parts described in this connection in theposition in which they are shown in Figure 12, from which it is evidentthat due to the lost-motion connection between lever I and link Hill,the division key 310 can be depressed without the slightest interferencefrom the means employed to return it to raised position.

I claim:

1. In a motor driven calculating machine, the combination with automaticcalculation control mechanism including a settable operation con trolmember; and a reversible registering mechanism including a settabledirection control member; of means controlled by said operation controlmember upon setting thereof for setting said direction control member,positively operable means actuated by the motor normally effective torestore said direction control mem her from set position, and meanscontrolled by said operation control member to render said positivelyoperable means ineffective upon set ting of said operation controlmember and to cause restoration of said positively operable means toeffective condition upon restoration of said operation control memberfrom set position.

2. In a motor driven calculating machine, the combination with mechanism"for conditioning said machine for a calculation, automatic calculationcontrol mechanism including a settable operation control member; and areversible registering mechanism including a settable direction controlmember; of means controlled by said operation control member uponsetting thereof for setting said direction control member, means ineluding said operation. control member for controlling said conditioningmechanism; positively operable means actuated by said conditioningmechanism normally constituting an operative connection between themotor and said direction control member to restore said directioncontrol member from set position, and means controlled by said operationcontrol member to disable said operative connection to render saidpositively operable means ineffective upon setting of said operationcontrol member and to reenable said operative connection to causerestoration of said positively operable means to effective conditionupon restoration of said operation control member from set position.

3. In a motor driven calculating machine, the

combination with automatic calculation control mechanism including asettable operation con trol member; and a reversible registeringmechanism including a settable direction control member; of meanscontrolled by said operation control member upon setting thereof forsetting said direction control member, means including said machine fora calculation, automatic calculation control mechanism including asettable operation control member; and a reversible registeringmechanism including a settable direction control member; of meanscontrolled by said operation control member upon setting thereof forsetting said direction control member, means including said operationcontrol member for controlling said conditioning mechanism; meansincluding a member actuated by said con ditioning mechanism through anoperative path of movement to restore said direction control member fromset position, and means controlled by said operation control member toguide said restoring member out of said operative path of movement uponsetting orsaid operation control member and to cause return of saidrestoring member to said operative path of movement upon rest-oration ofsaid operation control member from set position.

5. In a motor driven calculating machine, the combination with automaticcalculation mechanism including a settable operation control member;means for holdin mid operation control member in set position, and areversible registering mechanism including a settable direction controlmember; of means controlled by said operation control member uponsetting thereof for setting said direction control member, positivelyoperable means actuated by the motor for forming an operativeconnection-between the motor and said direction control member wherebyto restore said direction control member from set position, meanscontrolled by said operation control member upon setting thereof forrendering said positively operable means ineffective, means operable asan incident to termination of operation of the machine for releasingsaid operation control member from said holding means and restoring thesame from set position, and means controlled by said operation controlmember upon restoration thereof from set position for restoring saidpositively operable means to efiective condition 6. In a motor drivencalculating machine, the combination with automatic calculationmechanism including a settable operation control member; means forholding said operation control member in set position, and a reversibleregistering mechanism including a settable direction control member; ofmeans controlled by said operation control member upon setting thereoffor setting said direction control member, means including a memberactuated by the motor through an operative path or movement to restoresaid direction control member from set po-' sition, and means controlledby said operation control member to guide said restoring member out ofsaid operative path of movement upon setting of said operation controlmember and to cause return of said restoring member to said operativepath of movement upon restoration of said operation control member fromset position, and means operable as an incident to termination ofoperation of the machine for releasing said operation control memberfrom said holding means and restoring the same from set position.

7. In a motor driven calculating machine, the combination with mechanismfor conditioning said machine for a calculation, automatic calculationmechanism including a settable operation control member; means forholding said operation control member in set position, and

a reversible registering mechanism including a settable directioncontrol member; or means controlled by said operation control memberupon setting thereof for setting said direction control member, meansincluding said operation control member for controlling saidconditioning mechanism; positively operable means actuated by saidconditioning mechanism for forming an operative connection between themotor and said direction control member whereby to restore saiddirection control member from set position, means controlled by saidoperation control member upon setting thereof for rendering saidpositively operable means ineffective, means operable as an incident totermination of operation of the machine for releasing said operationcontrol member from said holding means, and means controlled by saidoperation control member upon restoration thereof from set position forrestoring said positively operable means to eifective condition.

8. In a motor driven calculating machine, the combination with mechanismfor conditioning said machine for a calculation, automatic calculationmechanism including a settable operation control member; means forholding said operation control member in set position, and a reversibleregistering mechanism including a settable direction control member; ofmeans controlled by said operation control member upon setting thereoffor setting said direction control member, means including saidoperation control member for controlling said conditioning mechanism;means including a member actuated by said conditioning mechanism throughan operative path of movement to restore said direction control memberfrom set position, means controlled by said operation control member toguide said restoring member out of said operative path of movement uponsetting of said operation control member and to cause return of saidrestoring member to said operative path 01 movement' upon restoration ofsaid operation control member from set position, and means operable asan incident to termination of operation of the machine for releasingsaid operation control member from said, holding means and restoring thesame from set position.

ROBERT E. BOYDEN.

